party/solo cup drainage

Hey Guys,

I'm using 18oz solo cups and I cut four 1/4in h. 3/4in w. for drainage at the very bottom sides of the cups.
The plants are a week old and i can see the roots have reached the bottom of the cup near the cut outs but haven't spread out.
I'm afraid the roots will grow out the drainage early and make it harder to transplant in 3 to 4 weeks.

Total of 10 plants from seeds. They are growing their second set of true leaves, noticed them about 2 day ago.

Should I transplant now to cups with drainage holes on the bottom, or let them be?

Best spot to cut for drainage?

I am a little confused. You are planning on transplanting to 3-5 gallon pots, right? If the roots are at the bottom of the solo cup and you can see them, it's time for a transplant, so do it now before they get root bound. At this point, you can transplant them to your final medium and pots.